• Basic Info
• Top Questions
• Clinical Info

What is this medicine?
LEVOTHYROXINE (lee voe thye ROX een) is a thyroid hormone. This medicine can improve symptoms of thyroid deficiency such as slow speech, lack of energy, weight gain, hair loss, dry skin, and feeling cold. It also helps to treat goiter (an enlarged thyroid gland).

This medicine may be used for other purposes; ask your health care provider or pharmacist if you have questions.

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What is the price of this medication and similar alternatives?

This pricing information is subject to change at the sole discretion of DS Pharmacy. This pricing information was updated 09/2009. For the most current and up-to-date pricing information, please visit www.drugstore.com. Actual costs to patients will vary depending on the use of specific retail or mail-order locations and health insurance copays.

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What side effects may I notice from receiving this medicine?
Side effects that you should report to your doctor or health care professional as soon as possible:

• difficulty breathing, wheezing, or shortness of breath
• chest pain
• excessive sweating or intolerance to heat
• fast or irregular heartbeat
• nervousness
• skin rash or hives
• swelling of ankles, feet, or legs
• tremors

Side effects that usually do not require medical attention (report to your doctor or health care professional if they continue or are bothersome):

• changes in appetite
• changes in menstrual periods
• diarrhea
• hair loss
• headache
• trouble sleeping
• weight loss

This list may not describe all possible side effects. Call your doctor for medical advice about side effects. You may report side effects to FDA at 1-800-FDA-1088.

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How should I use this medicine?
Take this medicine by mouth with plenty of water. It is best to take on an empty stomach, at least 30 minutes before or 2 hours after food. Follow the directions on the prescription label. Take at the same time each day. Do not take your medicine more often than directed.

Contact your pediatrician regarding the use of this medicine in children. While this drug may be prescribed for children and infants as young as a few days of age for selected conditions, precautions do apply. For infants, you may crush the tablet and place in a small amount of (5-10 ml or 1 to 2 teaspoonfuls) of water, breast milk, or non-soy based infant formula. Do not mix with soy-based infant formula. Give as directed.

Overdosage: If you think you have taken too much of this medicine contact a poison control center or emergency room at once.
NOTE: This medicine is only for you. Do not share this medicine with others.

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What if I miss a dose?
If you miss a dose, take it as soon as you can. If it is almost time for your next dose, take only that dose. Do not take double or extra doses.

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What may interact with this medicine?

• amiodarone
• antacids
• anti-thyroid medicines
• calcium supplements
• carbamazepine
• cholestyramine
• colestipol
• digoxin
• female hormones, including contraceptive or birth control pills
• iron supplements
• ketamine
• liquid nutrition products like Ensure
• medicines for colds and breathing difficulties
• medicines for diabetes
• medicines for mental depression
• medicines or herbals used to decrease weight or appetite
• phenobarbital or other barbiturate medications
• phenytoin
• prednisone or other corticosteroids
• rifabutin
• rifampin
• soy isoflavones
• sucralfate
• theophylline
• warfarin

This list may not describe all possible interactions. Give your health care provider a list of all the medicines, herbs, non-prescription drugs, or dietary supplements you use. Also tell them if you smoke, drink alcohol, or use illegal drugs. Some items may interact with your medicine.

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Who should NOT use this medication?

• Untreated subclinical (suppressed serum TSH concentrations with normal T₃ [triiodothyronine] and T₄ concentrations) or overt thyrotoxicosis of any etiology.
• AMI.
• Untreated adrenal insufficiency.
• Known hypersensitivity to any ingredient in the formulation. (See Sensitivity Reactions under Cautions.)

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What should I watch for while using this medicine?
Be sure to take this medicine with plenty of fluids. Some tablets may cause choking, gagging, or difficulty swallowing from the tablet getting stuck in your throat. Most of these problems disappear if the medicine is taken with the right amount of water or other fluids.

Do not switch brands of this medicine unless your health care professional agrees with the change. Ask questions if you are uncertain.

You will need regular exams and occasional blood tests to check the response to treatment. If you are receiving this medicine for an underactive thyroid, it may be several weeks before you notice an improvement. Check with your doctor or health care professional if your symptoms do not improve.

It may be necessary for you to take this medicine for the rest of your life. Do not stop using this medicine unless your doctor or health care professional advises you to.

This medicine can affect blood sugar levels. If you have diabetes, check your blood sugar as directed.

You may lose some of your hair when you first start treatment. With time, this usually corrects itself.

If you are going to have surgery, tell your doctor or health care professional that you are taking this medicine.

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What should I tell my health care provider before I take this medicine?
They need to know if you have any of these conditions:

• angina
• diabetes
• dieting or on a weight loss program
• fertility problems
• heart disease
• high levels of thyroid hormone
• pituitary gland problem
• previous heart attack
• an unusual or allergic reaction to levothyroxine, thyroid hormones, other medicines, foods, dyes, or preservatives
• pregnant or trying to get pregnant
• breast-feeding

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Can I stop taking the medication if I feel better?
As a general rule, you should always take your medications exactly as prescribed and do not change the dosage or stop taking the medication without first discussing it with your healthcare provider.

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I am on so many medications; do I have to take them all?
This is called polypharmacy—many different medications being used at the same time by one person. Sometimes, being on multiple medications is acceptable and appropriate but at other times it may be problematic. If you are receiving your medications from multiple physicians you need to ensure that they all know what medications you are taking. The best way to do this is to make a list of all the medications you are currently using, including all nutritional supplements, homeopathic remedies, vitamins and over-the-counter drugs (if possible, also include all the diseases you have been diagnosed with). Give a copy to every doctor who takes care of you so they have it on file, this way they can avoid duplicating medications and perhaps even try to consolidate some. After every doctor's visit remember to update the list accordingly. Also, as much as you possibly can, try to use the same pharmacy to fill all your prescriptions, this way any potential drug interactions can be caught and averted.

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Where can I get more information?
More Information

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